Causes of Swollen Lymph Nodes

Neck Nodes. The cervical (neck) nodes are most commonly involved. This is because of the many respiratory infections that occur during childhood.

Viral Throat Infection. This is the most common cause of swollen nodes in the neck. The swollen nodes are usually ½ to 1 inch (12 -25 mm) across. They are the same on each side.

Bacterial Throat Infection. A swollen node with a bacterial throat infection is usually just on one side. It can be quite large; over 1 inch (25 mm) across. This is about the size of a quarter. Most often, it's the node that drains the tonsil.

Tooth Decay or Abscess. This causes a swollen, tender node under the jawbone. Only one node is involved. The lower face may also be swollen on that side.

Armpit Swollen Nodes. Causes include skin infections (such as impetigo). A rash (such as poison ivy) can do the same.

Groin Swollen Nodes. Causes include skin infections (such as athlete's foot). A retained foreign object (such as a sliver) can be the cause.